RESUMEN
BACKGROUND: The purpose of this work was to further define the value of cardiac 31P magnetic resonance (MR) spectroscopy for patients with coronary artery disease and dilated cardiomyopathy. METHODS AND RESULTS: Blood-corrected and T1-corrected 31P MR spectra of anteroseptal myocardium were obtained at rest using image-selected in vivo spectroscopy localization, a selected volume of 85 +/- 12 cm3, and a field strength of 1.5 T. Nineteen volunteers had a creatine phosphate (CP)/ATP ratio of 1.95 +/- 0.45 (mean +/- SD) and a PDE/ATP ratio of 1.06 +/- 0.53; in four patients with left anterior descending coronary artery (LAD) stenosis, six patients with chronic anterior wall infarction, and four patients with chronic posterior wall infarction, CP/ATP and phosphodiester (PDE)/ATP ratios did not differ from those in volunteers. Twenty-five measurements of 19 patients with dilated cardiomyopathy yielded a CP/ATP of 1.78 +/- 0.51 and a PDE/ATP of 0.98 +/- 0.56 (p = NS versus volunteers). When these patients were grouped according to the severity of heart failure, however, CP/ATP was 1.94 +/- 0.43 in mild (p = NS versus volunteers) and 1.44 +/- 0.52 in severe DCM (p < 0.05), respectively. No correlation was found between CP/ATP and left ventricular ejection fraction or fractional shortening, but correlation of CP/ATP with the New York Heart Association (NYHA) class was significant (r = 0.60, p < 0.005). Six patients with dilated cardiomyopathy were studied repeatedly before and after 12 +/- 6 weeks of drug treatment leading to clinical recompensation with improvement of the NYHA status by 0.8 +/- 0.3 classes. Concomitantly, CP/ATP increased from 1.51 +/- 0.32 to 2.15 +/- 0.27 (p < 0.01), whereas PDE/ATP did not change significantly. CONCLUSIONS: Cardiac high-energy phosphate metabolism at rest is normal in LAD stenosis and chronic myocardial infarction in the absence of heart failure. The CP/ATP ratio has low specificity for the diagnosis of dilated cardiomyopathy. However, CP/ATP correlated with the clinical severity of heart failure and may improve during clinical recompensation.
Asunto(s)
Gasto Cardíaco Bajo/metabolismo , Cardiomiopatía Dilatada/diagnóstico , Enfermedad Coronaria/diagnóstico , Metabolismo Energético , Imagen por Resonancia Magnética , Fósforo , Adulto , Anciano , Cardiomiopatía Dilatada/metabolismo , Enfermedad Coronaria/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miocardio/metabolismo , Miocardio/patología , Fosfatos/metabolismo , Valores de ReferenciaRESUMEN
In a trial with 18 sows of the German landrace in three groups the dietary copper supply was varied in gravidity and lactation. Iron, copper, zinc, nickel and manganese concentration of milk was measured on 11 different days during the five weeks' lactation period in response to alimentary copper supply. Copper supply did not influence iron, zinc, and manganese concentration even if it was deficient during gravidity and lactation. Mature sow's milk contained 1.2 micrograms Fe, 1.5 micrograms Cu, 6-8 micrograms Zn, 0.16-0.23 microgram Ni and 0.07-0.13 microgram Mn per g fresh milk. First colostrum contained higher copper and zinc concentrations and lower concentrations of nickel and manganese compared to mature milk. Fe concentration remained constant. This investigation reproduced and completed thereby previous results. It was concluded that in copper deficiency status the interactions of copper with iron, zinc, nickel and manganese may not be effective for the excretion pathway milk.